Various techniques related to a touch panel are known. Japanese Patent Application Publication No. 2014-219961 discloses a sensing technique for improving resolution by detecting a touch operation position by simultaneously sensing two sets of signal lines (electrodes) (a pair of transmission signal lines and a pair of reception signal lines). Further, Japanese Patent Application Publication No. 2010-182277 discloses a so-called single layer structure in which there is no portion where electrodes intersect with each other in electrode wirings in X and Y directions.
It is important to maintain or improve sensing accuracy in the touch panel. In order to detect the operation, the signal lines of the touch panel are scanned. In the case of a capacitive type touch panel, a change or difference in a signal voltage is detected from the signal lines due to a capacitance change caused by a touch operation during the scanning. Therefore, the accuracy of the value serving as the reference for detecting the change or difference in the signal voltage affects the sensing accuracy of the touch panel operation.
In the present disclosure, it is considered to receive and detect reception signals from a pair of reception signal lines of the touch panel. Especially, a sensing operation including an operation of comparing levels of the reception signals from one reception signal line and the other reception signal line while sequentially switching a capacitance value of a measurement capacitance unit connected to the one reception signal line is performed. In this case, the accuracy of the sensing accuracy is improved by improving the accuracy of the capacitance value.